OPHTHALMOLOGICAL DRUGS AND EYEDROPS AND EYE OINTMENTS CLASSIFICATIONS @NURSESOUTLOOK

OPHTHALMOLOGY DRUGS

Ophthalmic drug administration is the administration of a drug through the eyes, most typically as an eye drop formulation.

What are eye drops?

Eye drops are a sterile solution or suspension of medicine. They are used to produce a local effect directly on the eye.

How to use your eye drops?

1. If your eye drops are a suspension,shake the bottle before using the drops.
2. Wash your hands.
3. Wipe eyes with a clean tissue to clear any residual wateriness or discharge.
4. Take the lid off the bottle.
5. Tip your head back.
6. Gently pull down your lower eyelid and look up.
7. Hold the dropper or bottle above the eye and gently squeeze one drop onto the inside of the lower eyelid, taking care not to touch the eye or eyelashes with the dropper or bottle.
8. Blink your eyes so the liquid spreads over the surface of the eyeball.
9. Wipe away any excess liquid with a clean tissue

Drop (Gutta)‐
Simplest and more convenient
Mainly for day time use
1 drop=50 microlitre
Conjuctival sac capacity=7‐13 micro liter
So, even 1 drop is more than enough
 

Measures to increase drop absorption:
‐Wait 5‐10 minutes between drops
‐Compress lacrimal sac
‐Keep lids closed for 5 minutes after instillation
50% drug remains 4 min. after instillation
10% drug reach aqueous humour
Compress NLD to decrease systemic absorption

How to use your eye ointment

1. Wash your hands.
2. Take the lid off the ointment.
3. Tip your head back.
4. Gently pull down your lower eyelid and look up.
5. Hold the tube above the eye and gently squeeze a 1cm line of ointment along the inside of the lower eyelid, taking care not to touch the eye or eyelashes with the tip of the tube.
6. Blink your eyes to spread the ointment over the surface of the eyeball.
7. Wipe away any excess ointment with a clean tissue
Your vision may be blurred when you open your eyes - DON'T rub your eyes. The blurring will clear after a few moments if you keep blinking.

COMMON OPHTHALMOLOGICAL DRUGS

Antibacterials (antibiotics)
Antivirals
Antifungal
Mydriatics and cycloplegics
Antiglaucoma
Anti‐inflammatory agents
Cortico Steroids And NSAIDS
Ocular Lubricants
Antihistaminics
Ocular diagnostic drugs
Local anesthetics
Corticosteroids NSAIDs


ANTIBACTERIALS (ANTIBIOTICS)


  Penicillins
¡Cephalosporins
 Sulfonamides
 Tetracyclines
 Chloramphenicol
 Aminoglycosides
 Fluoroquinolones
 Vancomycin


1. Used topically in prophylaxis (pre and
postoperatively) and treatment of
ocular bacterial infections.

2. Used orally for the treatment of
preseptal cellulitis  e.g. amoxycillin with clavulonate


1. Used intravenously for the treatment
of orbital cellulitis e.g. gentamicin, cephalosporin,vancomycin, flagyl
2. Can be injected intravitrally for the
treatment of endophthalmitis

CEPHALOSPORIN

1 st generation

Cephalothin, cefazolin, cephalexin
Active against G+ve and G‐ve
Not active against MRSA, Enterobacter, Proteus spp, P aeruginosa, Serratia, enterococci

2 nd generation

Cefamandole, cefoxitin, cefuroxime
Greater activity against G‐ve : H.influenzae, Enterobacter, Neisseria

3 rd generation

Cefotaxime, Ceftriaxone, Cefoperazone
Active against GNR > G+ve cocci : Serratia, Proteus, Ⱦ‐lactamase H influenzae, anaerobe
P.aeruginosa : ceftazidime, cefoperazone
Cefotaxime : good penetration blood‐ocular barrier

4 th generation

Extended spectrum
Against gram‐positive organisms as 1 st generation
Greater resistance to beta‐lactamases than 3 rd generation
Can cross blood brain barrier
Against nosocomial pathogens
Cefepime, Cefluprenam, Cefozopran, Cefpirome, Cefquinome

FLUOROQUINOLONES


1st generation
 ▪ Nalidixic acid

2nd generation

Ciprofloxacin,ofloxacin,    lomefloxacin
Active against G‐ including Pseudomonas spp, some G+
Not active against Strep pneumoniae

3rd generation
Levofloxacin
Same as 2nd
Active against more G+, Strep pneumoniae

4th generation

Gatifloxacin (Zymar®), moxifloxacin (Vigamox®)
Same as 3rd , active against anaerobe
Useful in bacterial conjunctivitis, corneal ulcer

AMINO GLYCOSIDES

Mainly against Gm negative bacilli
Bacterial protein synthesis inhibitors
Gentamycin—0.3% eye drop
Tobramycin‐ Pseudomonas 1% eye drop
Neomycin—0.3‐0.5% eye drop

TETRACYCLINE

Inhibit protein synthesis
Active against both gm+ and gm ‐, some fungi and Chlamydia

CHLOROMPHENICOL

Broad spectrum ,bacteriostatic, gm+/gm‐, Chlamydia
0.5% Eye drop, ointment


VANCOMYCIN
Against MRSA or strep
Useful in corneal ulcer, endophthalmitis
Polymyxin B + Neomycin
Against Staph. aureus, Strep spp, GNR
Useful in surface bacterial infection e.g. conjunctivitis, blepharitis

ANTIVIRALS


Acyclovir
Inhibits viral DNA synthesis
Active against HSV I & II, HZV
Oral, ointment
Interact with viral thymidine kinase (selective)
Used in herpetic keratitis


Ganciclovir
Active against CMV
Oral, iv, intravitreal
Useful in CMV retinitis
SE: BM suppression, renal failure
Used intravenously for CMV retinitis



Basic fungal classification

a. Filamentous fungi

Septate = Fusarium, Aspergillus
Nonseptate = Mucor
b. Yeasts

Candida, Cryptococcus

Most antifungal drugs act by attacking the membrane sterols of fungi (ergosterol), leaving mammalian sterols (cholesterol) unaffected


INDICATIONS

Fungal corneal ulcer
Fungal retinitis/ Endophthalmitis

Commonly used drugs are
Polyenes
Damage cell membrane of susceptible fungi E.g. Amphotericin B, Natamycin, nystatin
Side effect: nephrotoxicity
Imidazoles
Increase fungal cell membrane permeability
E.g. Miconazole, ketoconazole,fluconazole

⦁ Flucytocine
Act by inhibiting DNA synthesis
Dilate the pupil, ciliary muscle paralysis.

MYDYRIATICS AND CYCLOPLEGICS

Dilate the pupil, ciliary muscle paralysis
 Classification
Short acting‐ Tropicamide (4‐6 hours)
Intermediate‐ Homatropine ( 24 hours)
Long acting‐ Atropine (2 weeks)
 Indications
1. Corneal ulcer
2. Uveitis
3. Cycloplegic refraction


Directly acting agonists:
E.g. pilocarpine, acetylcholine (miochol), carbachol (miostat)
Uses: miosis, glaucoma
Mechanisms:
Miosis by contraction of the iris sphincter muscle
Increases aqueous outflow through the trabecular meshwork by longitudinal ciliary muscle contraction
Accommodation by circular ciliary muscle contraction
Side effects:

Local: diminished vision (myopia), headache, cataract, miotic cysts, and rarely retinal detachment
Systemic side effects: lacrimation, salivation, perspiration, bronchial spasm, urinary urgency, nausea, vomiting, and diarrhea


Indirectly acting: (anticholinesterases)
More potent with longer duration of action
Reversible inhibitors
E.g. Physostigmine
Used in glaucoma and lice infestation of lashes
Can cause CNS side effects

ANTIGLAUCOMA DRUGS

Mechanisms of action of antiglaucoma agents
The antiglaucoma agents act on the aqueous humor dynamics to reduce the intraocular pressure mainly by three mechanisms.
1. Decrease aqueous production in the ciliary body
2. Increase aqueous humor outflow through the trabecular meshwork
3. Increase aqueous humor outflow via the uveoscleral pathway.
Pharmacotherapy of Glaucoma

Prevention or modification of risk factors, particularly the raised intraocular pressure is the primary goal in the management of glaucoma. The disease needs to be managed medically, by laser therapy or by conventional
surgery as the case may be.

Classification of antiglaucoma agents
Depending on their route of administration antiglaucoma agents may be classified as
Topical drugs:
1. Cholinergic agents e.g. pilocarpine, carbachol,demecarium bromide and echothiophate iodide.
2. Adrenergic agonists e.g. epinephrine, dipivefrin,brimonidine and apraclonidine.
3. Beta blockers e.g. timolol, carteolol, betaxolol,levobunolol and metoprolol
4. Prostaglandin analogs e.g. PGF2α, latanoprost,
unoprostone and PHXA-85.
5. Carbonic anhydrase inhibitors e.g. dorzolamide
and brinzolamide.
Systemic drugs:
1. Carbonic anhydrase inhibitors e.g. acetazolamide and methazolamide.
2. Osmotic agents e.g. glycerine, mannitol and urea.

CORTICOSTEROIDS
Classification
1. Short acting
Hydrocortisone, cortisone, prednisolone
2. Intermediate acting
Triamcinolone, Fluprednisolone
3. Long acting
Dexamethasone ,betamethasone
INDICATIONS FOR CORTICOSTEROIDS
Topical

1. Allergic conjunctivitis,
2. Scleritis,
3. Uveitis,
4. allergic keratitis
5. After intraocular and extra ocular surgeries

Systemic (pathology behind the Lens)
1. Posterior uveitis
2. Optic neuritis
3. Corneal graft rejection


NEVER GIVE STEROID IFYOU ARE SUSPECTING ACTIVE INFECTION


SIDE EFFECTS OF CORTICOSTEROIDS
OCULAR

1. Glaucoma
2. Cataract
3. Activation of infection
4. Delayed wound healing

SYSTEMIC
1. Peptic ulcer
2. Hypertension
3. Increased blood sugar
4. Osteoporosis
5. Mental changes
6. Activation of tuberculosis and other infections




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